Dtc p0130 SUZUKI SWIFT 2000 1.G RG413 Service Workshop Manual

6-2 ENGINE GENERAL INFORMATION AND DIAGNOSIS
ENGINE DIAGNOSIS ......................................... 6-6
GENERAL DESCRIPTION ............................. 6-6
ON-BOARD DIAGNOSTIC SYSTEM
(VEHICLE WITH IMMOBILIZER INDICATOR
LAMP) ............................................................. 6-7
ON-BOARD DIAGNOSTIC SYSTEM
(VEHICLE WITHOUT IMMOBILIZER
INDICATOR LAMP) ...................................... 6-10
PRECAUTION IN DIAGNOSING
TROUBLE ..................................................... 6-11
ENGINE DIAGNOSTIC FLOW TABLE ......... 6-12
CUSTOMER PROBLEM INSPECTION
FORM (EXAMPLE) ................................... 6-14
MALFUNCTION INDICATOR LAMP (MIL)
CHECK...................................................... 6-15
DIAGNOSTIC TROUBLE CODE (DTC)
CHECK...................................................... 6-15
DIAGNOSTIC TROUBLE CODE (DTC)
CLEARANCE ............................................ 6-16
DIAGNOSTIC TROUBLE CODE (DTC)
TABLE ....................................................... 6-17
FAIL-SAFE TABLE.................................... 6-20
VISUAL INSPECTION .............................. 6-22
ENGINE BASIC INSPECTION.................. 6-23
ENGINE DIAGNOSIS TABLE ................... 6-26
SCAN TOOL DATA....................................... 6-31
INSPECTION OF ECM AND ITS
CIRCUITS ..................................................... 6-36
ECM VOLTAGE VALUES TABLE............. 6-37
TERMINAL RESISTANCE TABLE............ 6-43
COMPONENT LOCATION ........................... 6-45
TABLE A-1 MALFUNCTION INDICATOR
LAMP CIRCUIT CHECK - LAMP DOES NOT
COME “ON” AT IGNITION SWITCH ON
(BUT ENGINE AT STOP) ............................. 6-46
TABLE A-2 MALFUNCTION INDICATOR
LAMP CIRCUIT CHECK - LAMP REMAINS
“ON” AFTER ENGINE STARTS ................... 6-47
TABLE A-3 MIL CHECK - MIL FLASHES
AT IGNITION SWITCH ON (VEHICLE
WITHOUT IMMOBILIZER INDICATOR
LAMP) ........................................................... 6-48
TABLE A-4 MIL CHECK - MIL DOES NOT
FLASH OR JUST REMAINS ON EVEN
WITH GROUNDING DIAGNOSIS SWITCH
TERMINAL (VEHICLE WITHOUT
IMMOBILIZER INDICATOR LAMP) .............. 6-48
TABLE A-5 ECM POWER AND GROUND
CIRCUIT CHECK - MIL DOESN’T LIGHT
AT IGNITION SWITCH ON AND ENGINE
DOESN’T START THOUGH IT IS
CRANKED UP .............................................. 6-49
DTC P0105 (DTC NO.11) MANIFOLD
ABSOLUTE PRESSURE (MAP) CIRCUIT
MALFUNCTION ............................................ 6-52
DTC P0110 (DTC NO.18) INTAKE AIR
TEMP. (IAT) CIRCUIT MALFUNCTION ....... 6-55
DTC P0115 (DTC NO.19) ENGINE
COOLANT TEMPERATURE (ECT) CIRCUIT
MALFUNCTION ............................................ 6-57DTC P0120 (DTC NO.13) THROTTLE
POSITION CIRCUIT MALFUNCTION ........... 6-60
DTC P0121 THROTTLE POSITION CIRCUIT
RANGE/PERFORMANCE PROBLEM .......... 6-63
DTC P0130 (DTC NO.14) HEATED OXYGEN
SENSOR (HO2S) CIRCUIT MALFUNCTION
(SENSOR-1) .................................................. 6-66
DTC P0133 HEATED OXYGEN SENSOR
(HO2S) CIRCUIT SLOW RESPONSE
(SENSOR-1) .................................................. 6-68
DTC P0134 HEATED OXYGEN SENSOR
(HO2S) CIRCUIT NO ACTIVITY DETECTED
(SENSOR-1) .................................................. 6-69
DTC P0135 (DTC NO.14) HEATED OXYGEN
SENSOR (HO2S) HEATER CIRCUIT
MALFUNCTION (SENSOR-1) ....................... 6-70
DTC P0136 HEATED OXYGEN SENSOR
(HO2S) CIRCUIT MALFUNCTION
(SENSOR-2) .................................................. 6-72
DTC P0141 HEATED OXYGEN SENSOR
(HO2S) HEATER CIRCUIT MALFUNCTION
(SENSOR-2) .................................................. 6-74
DTC P0171 FUEL SYSTEM TOO LEAN ....... 6-76
DTC P0172 FUEL SYSTEM TOO RICH ....... 6-76
DTC P0300 RANDOM MISFIRE DETECTED
(MISFIRE DETECTED AT 2 OR MORE
CYLINDERS) ................................................. 6-81
DTC P0301 CYLINDER 1 MISFIRE
DETECTED ................................................... 6-81
DTC P0302 CYLINDER 2 MISFIRE
DETECTED ................................................... 6-81
DTC P0303 CYLINDER 3 MISFIRE
DETECTED ................................................... 6-81
DTC P0304 CYLINDER 4 MISFIRE
DETECTED ................................................... 6-81
DTC P0325 (DTC NO.17) KNOCK SENSOR
CIRCUIT MALFUNCTION ............................. 6-86
DTC P0335 (DTC NO.23) CRANKSHAFT
POSITION (CKP) SENSOR CIRCUIT
MALFUNCTION ............................................. 6-88
DTC P0340 (DTC NO.15) CAMSHAFT
POSITION (CMP) SENSOR CIRCUIT
MALFUNCTION ............................................. 6-91
DTC P0400 EXHAUST GAS
RECIRCULATION FLOW MALFUNCTION ... 6-94
DTC P0420 CATALYST SYSTEM
EFFICIENCY BELOW THRESHOLD ............ 6-97
DTC P0443 PURGE CONTROL VALVE
CIRCUIT MALFUNCTION ........................... 6-100
DTC P0480 RADIATOR COOLING FAN
CONTROL SYSTEM MALFUNCTION ........ 6-101
DTC P0500 (DTC NO.16) VEHICLE SPEED
SENSOR (VSS) MALFUNCTION ................ 6-103
DTC P0505 (DTC NO.26) IDLE CONTROL
SYSTEM MALFUNCTION ........................... 6-105
DTC P1450 BAROMETRIC PRESSURE
SENSOR LOW/HIGH INPUT....................... 6-108
DTC P1451 BAROMETRIC PRESSURE
SENSOR PERFORMANCE PROBLEM ...... 6-108

ENGINE GENERAL INFORMATION AND DIAGNOSIS 6-17
Without Using Scan Tool
1) Turn the ignition switch OFF position.
2) Disconnect battery negative cable for specified time below to
erase diagnostic trouble code stored in ECM memory and
reconnect it.
Time required to erase DTC :
DIAGNOSTIC TROUBLE CODE (DTC) TABLE
Ambient
temperatureTime to cut power to ECM
Over 0°C (32°F) 30 sec. or longer
Under 0°C
(32°F)Not specifiable.
Select a place with higher than 0°C
(32°F) temperature.
DTC
NO.DETECTING ITEM DETECTING CONDITION
(DTC will set when detecting :)MIL
(vehicle
with immo-
bilizer indi-
cator lamp)MIL
(vehicle
without
immobi-
lizer indica-
tor lamp)
P0105
(No.11)Manifold absolute pressure
circuit malfunctionLow pressure-high vacuum-low voltage
(or MAP sensor circuit shorted to ground)
High pressure-low vacuum-high voltage
(or MAP sensor circuit open)1 driving
cycle1 driving
cycle
P0110
(No.18)Intake air temp. circuit mal-
functionIntake air temp. circuit low input
Intake air temp. circuit high input1 driving
cycle1 driving
cycle
P0115
(No.19)Engine coolant temp. cir-
cuit malfunctionEngine coolant temp. circuit low input
Engine coolant temp. circuit high input1 driving
cycle1 driving
cycle
P0120
(No.13)Throttle position circuit mal-
functionThrottle position circuit low input
Throttle position circuit high input1 driving
cycle1 driving
cycle
P0121 Throttle position circuit per-
formance problemPoor performance of TP sensor 2 driving
cyclesNot
applicable
P0130
(No.14)HO2S circuit malfunction
(Sensor-1)Min. output voltage of HO2S-higher than
specification
Max. output voltage of HO2S-lower than
specification2 driving
cycle1 driving
cycle
P0133 HO2S circuit slow response
(Sensor-1)Response time of HO2S-1 output voltage
between rich and lean is longer than spec-
ification.2 driving
cyclesNot
applicable
P0134 HO2S circuit no activity
detected (Sensor-1)Output voltage of HO2S-1 fails to go above
specification (or HO2S-1 circuit shorted to
ground).2 driving
cycles1 driving
cycle
P0135
(No.14)HO2S heater circuit mal-
function (Sensor-1)Terminal voltage is lower than specifica-
tion at heater OFF or it is higher at heater
ON.2 driving
cycles1 driving
cycle
P0136 HO2S circuit malfunction
(Sensor-2)Max. voltage of HO2S-2 is lower than
specification or its min. voltage is higher
than specification2 driving
cyclesNot
applicable

6-20 ENGINE GENERAL INFORMATION AND DIAGNOSIS
FAIL-SAFE TABLE
When any of the following DTCs is detected, ECM enters fail-safe mode as long as malfunction continues to
exist but that mode is canceled when ECM detects normal condition after that.P1620
(No.84)ECU code not registered
Refer to Section 8G P1621
(No.83)No ECU code transmitted from Immobilizer
Control Module
P1622
(No.82)Fault in ECM
P1623
(No.81)ECU code not matched DTC NO. DETECTING ITEM DETECTING CONDITION
(DTC will set when detecting :)MIL
NOTE:
For (
) marked No. in DTC column, it is used for vehicle without immobilizer indication lamp.
DTC No.12 appears when none of the other codes is identified.
For vehicle with immobilizer indication lamp, star (
✱) marked DTCs can be read with SUZUKI scan
tool ECM application.
DTC NO. TROUBLE AREA FAIL-SAFE OPERATION SYMPTOM
P0105
(No.11)MAP SENSOR ECM uses value determined by throt-
tle opening and engine speed.
ECM stops EGR, EVAP purge and
idle air control.Hard starting/ rough or incorrect
idle/ excessive fuel consumption/
hesitation/ poor acceleration/
surge/ detonation or spark knock
P0110
(No.18)IAT SENSOR ECM controls actuators assuming
that intake air temperature is 20°C.Hard starting/ rough or incorrect
idle/ excessive fuel consumption/
hesitation poor acceleration/ deto-
nation or spark knock
P0115
(No.19)ECT SENSOR ECM controls actuators assuming
that engine coolant temperature is
80°C.
Radiator fan motor ON.Hard starting/ rough or incorrect
idle/ excessive fuel consumption/
hesitation poor acceleration/ deto-
nation or spark knock
P0120
(No.13)TP SENSOR ECM controls actuators assuming
that throttle opening is 20°.Rough or incorrect idle/ excessive
fuel consumption/ hesitation/ poor
acceleration
P0130,
P0134
(No.14)HEATED OXYGEN
SENOR-1–Hard starting/rough or incorrect
idle/ excessive fuel consumption/
hesitation/ poor acceleration
P0325
(No.17)KNOCK SENSOR–Detonation/ spark knock
P0335
(No.23)CKP SENSORFix ignition timing.
ECM changes injection control sys-
tem from sequential injection to
simultaneous one.Hard staring/ engine stall

ENGINE GENERAL INFORMATION AND DIAGNOSIS 6-37
ECM VOLTAGE VALUES TABLE
For TYPE A (See NOTE)
NOTE:
Type A is other than follows.
Type B is right hand steering vehicle equipped with fasten seat belt light and immobilizer control sys-
tem.
TERMINAL NO. CIRCUIT NORMAL VOLT-
AGECONDITION
C421 Ground––
2 Ground––
3 Ground––
4 EVAP canister purge valve 10 – 14 V Ignition switch ON
5 Engine coolant temp. and barometric
pressure signal for TCM (A/T)Indication
deflection
repeated 0 V
and 10 – 14 VIgnition switch ON
6 Idle air control valve 0 – 13 V At specified idle speed after engine warmed up
7 Heater of HO2S-1 (if equipped) 10 – 14 V Ignition switch ON
8 Fuel injector NO.4 10 – 14 V Ignition switch ON
9 Fuel injector NO.1 10 – 14 V Ignition switch ON
10 Sensor ground––
11 Camshaft position sensor 0 – 0.8 V and
4 – 6 VIgnition switch ON
12 Knock sensor (if equipped) 2.1 - 2.9 V Ignition switch ON
13 Heated oxygen sensor-1 (if equipped) Refer to DTC P0130 diag. flow table
CO adjusting resistor (if equipped)––
14 Engine coolant temp. sensor 0.55 - 0.95 V Ignition switch ON
Engine coolant temp. : 80°C (176°F)
15 Intake air temp. sensor 2.0 – 2.7 V Ignition switch ON
Intake air temp. : 20°C (68°F)
16 Test switch terminal (Vehicle without
immobilizer indicator lamp)4 – 6 V Ignition switch ON
17 Electric load signal (+) 0V Ignition switch ON
Small light and rear defogger OFF
10 – 14 V Ignition switch ON
Small light and rear defogger ON
18 A/C triple pressure switch 10 – 14 V A/C not operated
19 Ignition coil #2––
20 Ignition coil #1––
21 Fuel injector NO.2 10 – 14 V Ignition switch ON
22 Power source for sensor 4.75 – 5.25 V Ignition switch ON
23 Crankshaft position sensor––
24–– –
25 Shield ground––
26 Manifold absolute pressure sensor 3.3 – 4.0 V Ignition switch ON
Barometric pressure : 100 kPa (760 mmHg)
27 Diag. Switch terminal (Vehicle without
immobilizer indicator lamp)4 – 6 V Ignition switch ON
28 Monitor output (Vehicle without immo-
bilizer indicator lamp)––
29 Blank––
30 Blank––
31 Fuel injector NO.3 10 – 14 V Ignition switch ON

6-38 ENGINE GENERAL INFORMATION AND DIAGNOSIS
TERMINAL
NO.CIRCUIT NORMAL
VOLTAGECONDITION
C411 A/C compressor clutch 0 V Ignition switch ON
2 EGR valve (stepper motor coil 1)
(if equipped)10 – 14 V Ignition switch ON
3 Throttle position sensor 0.2 – 1.0 V Ignition switch ON
Throttle valve at idle position
2.8 – 4.8 V Ignition switch ON
Throttle valve at full open position
4 Heater of HO2S-2
(Vehicle with immobilizer indicator lamp)10 – 14 V Ignition switch ON
5 Power source 10 – 14 V Ignition switch ON
6 Power source 10 – 14 V Ignition switch ON
7 Engine start switch
(Engine start signal)6 – 12 V While engine cranking
0 V Other than above
8 EGR valve (stepper motor coil 3)
(if equipped)10 – 14 V Ignition switch ON
9 EGR valve (stepper motor coil 2)
(if equipped)10 – 14 V Ignition switch ON
10 Main relay 10 – 14 V Ignition switch OFF
0.4 – 1.5 V Ignition switch ON
11 Blank––
12 Blank––
13 Heated oxygen sensor-2
(Vehicle with immobilizer indicator lamp)Refer to DTC P0130 diag. flow table
14 D-range ID-up signal (A/T) 10 – 14 V Ignition switch ON
15 R-range signal (A/T) 0 V Ignition switch ON
16 A/C (input) signal 10 – 14 V Ignition switch ON
A/C switch OFF
0 – 2 V Ignition switch ON
A/C switch ON
17 EGR valve (stepper motor coil 4)
(if equipped)10 – 14 V Ignition switch ON
18 Radiator fan control relay 10 – 14 V Ignition switch ON
Engine coolant temp. : 9.5°C or
lower (203°F)
0 – 1 V Ignition switch ON
Engine coolant temp. : 97.5°C
(208°F) or higher
19 Fuel pump relay 0 – 1 V For 2 seconds after ignition switch
ON
10 – 14 V After the above time
20–––

6-40 ENGINE GENERAL INFORMATION AND DIAGNOSIS
For TYPE B (For applicable mode, refer to NOTE in “ECM VOLTAGE VALUES TABLE”) G02 17 Power source for back-up 10 – 14 V Anytime
TERMINAL NO. CIRCUIT NORMAL VOLT-
AGECONDITION
C421Ground––
2Ground––
3Ground––
4 EVAP canister purge valve 10 – 14 V Ignition switch ON
5–– –
6 Idle air control valve 0 – 13 V At specified idle speed after engine warmed up
7 Heater of HO2S-1 (if equipped) 10 – 14 V Ignition switch ON
8 Fuel injector NO.4 10 – 14 V Ignition switch ON
9 Fuel injector NO.1 10 – 14 V Ignition switch ON
10 Sensor ground––
11 Camshaft position sensor 0 – 0.8 V and
4 – 6 VIgnition switch ON
12 Shield ground––
13 Heated oxygen sensor-1 (if equipped) Refer to DTC P0130 diag. flow table
CO adjusting resistor (if equipped)––
14 Engine coolant temp. sensor 0.55 - 0.95 V Ignition switch ON
Engine coolant temp. : 80°C (176°F)
15 Intake air temp. sensor 2.0 – 2.7 V Ignition switch ON
Intake air temp. : 20°C (68°F)
16 Throttle position sensor 0.2 – 1.0 V Ignition switch ON
Throttle valve at idle position
2.8 – 4.8 V Ignition switch ON
Throttle valve at full open position
17 EGR valve (stepper motor coil 3)
(if equipped)10 – 14 V Ignition switch ON
18 EGR valve (stepper motor coil 1)
(if equipped)10 – 14 V Ignition switch ON
19 Ignition coil #2––
20 Ignition coil #1––
21 Fuel injector NO.2 10 – 14 V Ignition switch ON
22 Power source for sensor 4.75 – 5.25 V Ignition switch ON
23 Crankshaft position sensor––
24–– –
25 knock sensor (if equipped) 2.1 – 2.9 V Ignition switch ON
26 Manifold absolute pressure sensor 3.3 – 4.0 V Ignition switch ON
Barometric pressure : 100 kPa (760 mmHg)
27–– –
28 EGR valve (stepper motor coil 4)
(if equipped)10 – 14 V Ignition switch ON
29 EGR valve (stepper motor coil 2)
(if equipped)10 – 14 V Ignition switch ON
30 A/C triple pressure switch 10 – 14 V A/C not operated
31 Fuel injector NO.3 10 – 14 V Ignition switch ON
TERMINAL
NO.CIRCUIT NORMAL
VOLTAGECONDITION

6-66 ENGINE GENERAL INFORMATION AND DIAGNOSIS
DTC P0130 (DTC NO.14) HEATED OXYGEN SENSOR (HO2S) CIRCUIT MAL-
FUNCTION (SENSOR-1)
WIRING DIAGRAM / CIRCUIT DESCRIPTION
DTC CONFIRMATION PROCEDURE
1) Turn ignition switch OFF. Clear DTC with ignition switch ON, check vehicle and environmental condition for :
–Altitude (barometric pressure) : 2400 m, 8000 ft or less (560 mmHg, 75 kPa or more)
–Ambient temp. : –10°C, 14°F or higher
–Intake air temp. : 70°C, 158°F or lower
2) Warm up engine to normal operating temperature.
3) Drive vehicle at 30 – 40 mph, 50 – 60 km/h for 2 min.
4) Stop vehicle and run engine at idle for 2 min.
5) Check DTC in “DTC” mode and pending DTC in “ON BOARD TEST” or “PENDING DTC” mode.
ECM
WHT
ORNC42-10 C42-13
E11
C42 (31P) C41 (24P) G02 (17P)1 2 3 4 5 6 7 8 9
10 11 12 13 14 15 16 17 18 19 20 21
22 23 24 25 26 28 27 29 30 315 6
1 2 3 4 5 6 7
11 12
9 10 11 13 12 14 15 16
16 171 2
7 8
13 14 3 4
9 10
15 17 188
19 20 21 22 23 24
DTC DETECTING CONDITION POSSIBLE CAUSE
When running at idle speed after engine warmed up and
running at specified vehicle speed, HO2S-1 output volt-
age does not go below 0.3 V or over 0.6 V.
✱2 driving cycle detection logic, Monitoring once/1 driving.Heated oxygen sensor-1 malfunction
“WHT” or “ORN” circuit open (poor connection)
or short
WARNING:
When performing a road test, select a place where there is no traffic or possibility of a traffic acci-
dent and be very careful during testing to avoid occurrence of an accident.
Road test should be carried out with 2 persons, a driver and a tester.

ENGINE GENERAL INFORMATION AND DIAGNOSIS 6-67
INSPECTION
Fig. 1 for Step 3
Fig. 2 for Step 3Step Action Yes No
1Was “ENGINE DIAG. FLOW TABLE” per-
formed?Go to Step 2. Go to “ENGINE DIAG.
FLOW TABLE”.
2 Is there DTC(s) other than HO2S-1 (DTC
P0130)?Go to applicable DTC
Diag. Flow Table.Go to Step 3.
3 Check HO2S-1 signal.
1) Connect scan tool to DLC with ignition
switch OFF.
2) Warm up engine to normal operating tem-
perature and keep it at 2000 r/min. for 60
sec.
3) Repeat racing engine (Repeat depressing
accelerator pedal 5 to 6 times continuously
and take foot off from pedal to enrich and
enlean A/F mixture). See Fig. 1 and 2.
Does HO2S-1 output voltage deflect between
0.3 V and over 0.6 V repeatedly?Intermittent trouble.
Check for intermittent
referring to “Intermittent
and Poor Connection” in
Section 0A.Check “WHT” and “ORN”
wires for open and short,
and connections for poor
connection.
If wires and connections
are OK, replace HO2S-1.

6-68 ENGINE GENERAL INFORMATION AND DIAGNOSIS
DTC P0133 HEATED OXYGEN SENSOR (HO2S) CIRCUIT SLOW RESPONSE
(SENSOR-1)
WIRING DIAGRAM / CIRCUIT DESCRIPTION
Refer to DTC P0130 section.
Fig. 1
DTC CONFIRMATION PROCEDURE
Refer to DTC P0130 section.
INSPECTION
DTC DETECTING CONDITION POSSIBLE CAUSE
When running at specified idle speed after engine warmed up and
running at specified vehicle speed, response time (time to change
from lean to rich or from rich to lean) of HO2S-1 output voltage is
about 1 sec. at minimum or average time of 1 cycle is 5 sec. at
minimum. See. Fig. 1
✱2 driving cycle detection logic, Monitoring once/1 driving.Heated oxygen sensor-1 malfunction
Step Action Yes No
1Was “ENGINE DIAG. FLOW TABLE” per-
formed?Go to Step 2. Go to “ENGINE DIAG.
FLOW TABLE”.
2 Is there DTC(s) other than HO2S-1 (DTC
P0133)?Go to applicable DTC
Diag. Flow Table.Replace HO2S-1.

ENGINE GENERAL INFORMATION AND DIAGNOSIS 6-69
DTC P0134 HEATED OXYGEN SENSOR (HO2S) CIRCUIT NO ACTIVITY
DETECTED (SENSOR-1)
WIRING DIAGRAM / CIRCUIT DESCRIPTION
Refer to DTC P0130 section.
DTC CONFIRMATION PROCEDURE
Refer to DTC P0131 section.
INSPECTION
Fig. 1 for Step 3DTC DETECTING CONDITION POSSIBLE CAUSE
Engine warmed up.
While running under other than high load and high engine speed
conditions or at specified idle speed (engine is in closed loop con-
dition), HO2S-1 output voltage is high or low continuously.
✱2 driving cycle detection logic, Continuous monitoring.“WHT” or “ORN” circuit open or short
Heated oxygen sensor malfunction
Fuel system malfunction
Exhaust gas leakage
Step Action Yes No
1Was “ENGINE DIAG. FLOW TABLE” per-
formed?Go to Step 2. Go to “ENGINE DIAG.
FLOW TABLE”.
2 Is there DTC(s) other than Fuel system
(DTC P0171/P0172) and HO2S-1 (DTC
P0134)?Go to applicable DTC
Diag. Flow Table.Go to Step 3.
3 Check HO2S-1 and Its Circuit.
1) Connect scan tool to DLC with ignition
switch OFF.
2) Warm up engine to normal operating tem-
perature and keep it at 2000 r/min. for 60
sec.
3) Repeat racing engine (Repeat depressing
accelerator pedal 5 to 6 times continuously
and take foot off from pedal to enrich and
enlean A/F mixture). See Fig. 1.
Does HO2S-1 output voltage deflect between
0.3V and over 0.6V repeatedly?Go to DTC P0171 and
P0172 Diag. Flow Table
(Fuel System Check).Check “WHT” and “ORN”
wires for open and short,
and connections for poor
connection. If wires and
connections are OK,
replace HO2S-1.